1. Technical Field
The present invention relates to a polarization device, a method of manufacturing the polarization device, a liquid crystal device, and an electronic apparatus.
2. Related Art
As a light modulating device in various electro-optical apparatuses, a liquid crystal device has been used. As a structure of the liquid crystal device, a structure in which a liquid crystal layer is interposed between a pair of substrates oppositely disposed has been widely known. In addition, a configuration, which includes a polarization device that allows a predetermined polarized light to be incident to the liquid crystal layer, and an alignment film that controls an arrangement of liquid crystal molecules at the time of not applying a voltage, is typical.
As the polarization device, a film-type polarization device manufactured by extending a resin film including iodine or a dichroic dye in one direction and aligning the iodine or dichroic dye in this extension direction, and a wire grid type polarization device formed by lining a nano-scaled metal fine wire on a transparent substrate are known.
The wire grid type polarization device is made from an inorganic material, such that the polarization device has the merit of superior heat resistance, and is used in a field where heat resistance is especially necessary. For example, the polarization device is used as a polarization device for a light valve of a liquid crystal projector. As such a wire grid type polarization device, for example, there is disclosed a technique described in JP-A-10-73722. In addition, as a wire grid type polarization device in which a reflectance is suppressed, for example, there is disclosed a technique described in JP-A-2010-72591.
In JP-A-10-73722, a metal lattice on a substrate is oxidized by a heat treatment and thereby an oxide film is formed on the metal lattice surface, such that it is possible to provide a polarization device having superior environment resistance. However, in a method disclosed in JP-A-10-73722, a substrate is processed at a temperature of 500° C. or higher, such that cracking or deformation of the substrate is apt to occur. In addition, the metal lattice itself is damaged by heat expansion, and thereby dimension of the metal lattice, such as height and width, which determines a characteristic of the polarization device is changed. Therefore, there is a problem that a polarization characteristic of the polarization device, which is entirely uniform, cannot be shown. Furthermore, there is a problem that when the temperature is raised at the time of operating the liquid crystal device, the property of the metal lattice is changed, such that the polarization characteristic is lowered.
In JP-A-2010-72591, a method of manufacturing a wire grid type polarization device in which a light absorbing layer is provided on a light reflecting layer is disclosed, but there is not disclosed a method of manufacturing a wire grid type polarization device, in which an oxidized film is provided on a top face and side faces of the light reflecting layer, and a light absorbing layer is provided on the oxidized film.